/*
 * CamelCaseBuilder.java July 2008
 *
 * Copyright (C) 2008, Niall Gallagher <niallg@users.sf.net>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

package wx.xml.simpleframework.xml.stream;

/**
 * The <code>CamelCaseBuilder</code> is used to represent an XML style
 * that can be applied to a serialized object. A style can be used to
 * modify the element and attribute names for the generated document.
 * This styles can be used to generate camel case XML.
 * <pre>
 *
 *    &lt;ExampleElement&gt;
 *        &lt;ChildElement exampleAttribute='example'&gt;
 *           &lt;InnerElement&gt;example&lt;/InnerElement&gt;
 *        &lt;/ChildElement&gt;
 *     &lt;/ExampleElement&gt;
 *
 * </pre>
 * Above the camel case XML elements and attributes can be generated
 * from a style implementation. Styles enable the same objects to be
 * serialized in different ways, generating different styles of XML
 * without having to modify the class schema for that object.
 *
 * @author Niall Gallagher
 */
class CamelCaseBuilder implements Style {

    /**
     * If true then the attribute will start with upper case.
     */
    protected final boolean attribute;

    /**
     * If true then the element will start with upper case.
     */
    protected final boolean element;

    /**
     * Constructor for the <code>CamelCaseBuilder</code> object. This
     * is used to create a style that will create camel case XML
     * attributes and elements allowing a consistent format for
     * generated XML. Both the attribute an elements are configurable.
     *
     * @param element   if true the element will start as upper case
     * @param attribute if true the attribute starts as upper case
     */
    public CamelCaseBuilder(boolean element, boolean attribute) {
        this.attribute = attribute;
        this.element = element;
    }

    /**
     * This is used to generate the XML attribute representation of
     * the specified name. Attribute names should ensure to keep the
     * uniqueness of the name such that two different names will
     * be styled in to two different strings.
     *
     * @param name this is the attribute name that is to be styled
     * @return this returns the styled name of the XML attribute
     */
    public String getAttribute(String name) {
        if (name != null) {
            return new Attribute(name).process();
        }
        return null;
    }

    /**
     * This is used to generate the XML element representation of
     * the specified name. Element names should ensure to keep the
     * uniqueness of the name such that two different names will
     * be styled in to two different strings.
     *
     * @param name this is the element name that is to be styled
     * @return this returns the styled name of the XML element
     */
    public String getElement(String name) {
        if (name != null) {
            return new Element(name).process();
        }
        return null;
    }

    /**
     * This is used to parse the style for this builder. This takes
     * all of the words split from the original string and builds all
     * of the processed tokens for the styles elements and attributes.
     *
     * @author Niall Gallagher
     */
    private class Attribute extends Splitter {

        /**
         * This determines whether to capitalise a split token
         */
        private boolean capital;

        /**
         * Constructor for the <code>Attribute</code> object. This will
         * take the original string and parse it such that all of the
         * words are emitted and used to build the styled token.
         *
         * @param source this is the original string to be parsed
         */
        private Attribute(String source) {
            super(source);
        }

        /**
         * This is used to parse the provided text in to the style that
         * is required. Manipulation of the text before committing it
         * ensures that the text adheres to the required style.
         *
         * @param text this is the text buffer to acquire the token from
         * @param off  this is the offset in the buffer token starts at
         * @param len  this is the length of the token to be parsed
         */
        @Override
        protected void parse(char[] text, int off, int len) {
            if (attribute || capital) {
                text[off] = toUpper(text[off]);
            }
            capital = true;
        }

        /**
         * This is used to commit the provided text in to the style that
         * is required. Committing the text to the buffer assembles the
         * tokens resulting in a complete token.
         *
         * @param text this is the text buffer to acquire the token from
         * @param off  this is the offset in the buffer token starts at
         * @param len  this is the length of the token to be committed
         */
        @Override
        protected void commit(char[] text, int off, int len) {
            builder.append(text, off, len);
        }
    }

    /**
     * This is used to parse the style for this builder. This takes
     * all of the words split from the original string and builds all
     * of the processed tokens for the styles elements and attributes.
     *
     * @author Niall Gallagher
     */
    private class Element extends Attribute {

        /**
         * This determines whether to capitalise a split token
         */
        private boolean capital;

        /**
         * Constructor for the <code>Element</code> object. This will
         * take the original string and parse it such that all of the
         * words are emitted and used to build the styled token.
         *
         * @param source this is the original string to be parsed
         */
        private Element(String source) {
            super(source);
        }

        /**
         * This is used to parse the provided text in to the style that
         * is required. Manipulation of the text before committing it
         * ensures that the text adheres to the required style.
         *
         * @param text this is the text buffer to acquire the token from
         * @param off  this is the offset in the buffer token starts at
         * @param len  this is the length of the token to be parsed
         */
        @Override
        protected void parse(char[] text, int off, int len) {
            if (element || capital) {
                text[off] = toUpper(text[off]);
            }
            capital = true;
        }
    }

}
